Lake Hamun (
Daryacheh-ye Hamun) or
Hamoun Oasis is a term applied to
wetlands in
endorheic Sistan Basin on the
Irano-
Afghan border.
Hamun is generic term which refers to shallow lakes (or lagoons), usually seasonal, that occur in deserts of southeast Iran and adjacent areas of Afghanistan and
Pakistan as product of
snowmelt in nearby mountains in spring. The term Hamun Lake (or Lake Hamun) is equally applied to
Hamun-e Helmand (entirely in Iran), as well to shallow lakes Hamun-e Sabari and Hamun-e Puzak, which extend into territory of present-day Afghanistan with latter being almost entirely inside Afghanistan. The Hamun is fed by numerous seasonal water tributaries; the main tributary is the
perennial Helmand River, which originates in Afghanistan
Hindu Kush mountains. In modern times, and prior to the existence of the dams for agricultural irrigation, spring floods would bring into existence much larger lakes.